GENG Peihao, QIN Guoliang, MA Hong, et al.Heat Transfer and Material Flow in Friciton Stir Lap Welding ofAl Alloy/ Steel[J].Electric Welding Machine, 2023, 53(3): 1-14. DOI： 10.7512/j.issn.1001-2303.2023.03.01.
Heat Transfer and Material Flow in Friciton Stir Lap Welding of Al Alloy/ Steel
The heat transfer and material flow behavior during friction stir lap welding (FSLW) of Al alloy 5052 and high-strength steel DP590 were numerically simulated based on the coupled Euler-Lagrangian finite element method (CEL-FEM). The predicted results of the temperature histories and the deformation profile of the weld matched well with the experimental measurements. The simulation results show that when the welding speed is kept constant at 300 mm/min, as the rotation speed increases from 500 r/min to 1 000 r/min, the peak temperature position of the stirring zone is transferred from the Al alloy surface behind the shoulder on the advancing side (AS) to the bottom of the stirring pin, that is, the interface of the steel stirring zone. Meanwhile, the peak temperature increases from 545 °C to 635 °C during the welding process. Regardless of rotation speed, the temperature on the AS is always higher than that of the retreating side (RS). The material migration was studied by the tracer particle method. The Al alloy materials on the AS are eventually transferred to the rear region of the AS, bypassing the RS via the inner shear region, which is close to the stirring pin and shoulder root. The Al alloy materials on the RS were mainly migrated to the ipsilateral rear, and the migration trajectory is more divergent. The stirring pin acts on the Al/steel overlapping surface, driving the steel materials on the AS to move to the RS rear of the stirring pin and simultaneously extruding the steel materials into the Al weld area in the vertical direction. The steel material that migrates from the AS to the RS as the pin rotates eventually causes the RS to form a larger-sized hook-like structure. Compared with the Al alloy side, the increase in rotating speed more significantly enhances the material flow on the steel surface.
friction stir weldingdissimilar joiningfinite element simulationtemperaturematerial flow
Christy J V， MOURAD A H， Sherif M M， et al. Review of recent trends in friction stir welding process of aluminum alloys and aluminum metal matrix composites［J］. Transactions of Nonferrous Metals Society of China，2021，31（11）：3281-309.
Liu F C， Hovanski Y， Miles M P，et al. A review of friction stir welding of steels： Tool， material flow， microstructure，and properties［J］. Journal of Materials Science & Technology， 2018 ，34（1）：39-57.
Meschut G， Janzen V， Olfermann T. Innovative and highly productive joining technologies for multi-material lightweight car body structures［J］. Journal of Materials Engineering and Performance， 2014，23（5）：1515-23.
Wan L， Huang Y. Friction stir welding of dissimilar aluminum alloys and steels： a review［J］. The International Journal of Advanced Manufacturing Technology， 2018 ，99（5）：1781-811.
Simar A， Avettand-Fènoël MN. State of the art about dissimilar metal friction stir welding［J］. Science and Technology of Welding and Joining， 2017，22（5）：389-403.
Hussein S A， Hadzley A B. Characteristics of aluminum-to-steel joint made by friction stir welding： A review［J］. Materials Today Communications，2015，5：32-49.
HUANG X， ZHOU L， JIANG J J， et al. Effect of Friction Stir Welding Parameters on Microstructure and Mechanical Properties of Ultra-thin Aluminium Alloy Plate/high Strength Steel Lap Joints［J］. Nonferrous Metal Materials And Engineering，2019，40（1）：13-19.
DU Y F， BAI J B， TIAN Z J， et al. Investigation on three-dimensional real coupling numerical simulation of temperature field of friction stir welding of 2219 aluminum alloy［J］. Transactions of The China Welding Institution， 2014， 35（8）： 57-60，70.
Gao E Z， Zhang X X， Liu C Z. Numerical simulations on material flow behaviors in whole process of friction stir welding［J］. Transactions of Nonferrous Metals Society of China， 2018， 28（11）：2324-34.
WU C S， SU H， SHI L. Numerical Simulation of Heat Generation， Heat Transfer and Material Flow in Friction Stir Welding［J］. Acta Metall Sin， 2018， 54（2）： 265-277.
Meyghani B， WU C S. Progress in Thermomechanical Analysis of Friction Stir Welding［J］. Chin. J. Mech. Eng.， 2020（12）：1-33.
Das D， Bag S， Pal S. A finite element model for surface and volumetric defects in the FSW process using a coupled Eulerian–Lagrangian approach［J］. Science and Technology of Welding and Joining， 2021， 26（5）：412-9.
Geng P， Ma Y， Ma N， et al. Effects of rotation tool-induced heat and material flow behaviour on friction stir lapped Al/steel joint formation and resultant microstructure［J］. International Journal of Machine Tools and Manufacture， 2022，174：103858.
Benson D J. A mixture theory for contact in multi-material Eulerian formulations［J］. Comput. Methods Appl. Mech. Eng.， 1997， 140 （1-2）： 59-86.
Zhang X X， Xiao B L， Ma Z Y. A transient thermal model for friction stir weld. Part I： the model［J］. Metall. Mater. Trans. ，2011， 42 （10） ： 3218-3228.
Jalili N， Tabrizi H B， Hosseini M M. Experimental and numerical study of simultaneous cooling with CO2 gas during friction stir welding of Al-5052［J］. Mater. Process. Technol.， 2016， 237： 243-253.
Zhang G， Li Y， Lin Z. Evolution mechanism of geometry morphology for metallic bump assisted resistance spot welded （MBaRSW） joints［J］. Manuf. Process， 2020， 59： 432-443.